High speed current collection

ABSTRACT

The coupling between a high speed electrically powered vehicle and an overhead catenary wire current distribution system is enhanced by elastic coupling means which parallels and thus provides for uniformity of movement of oppositely disposed ends of a support portion of a pantograph-bow collector linkage system when the inclination of the system to the horizontal exceeds a predetermined limit.

United States Patent [1 1 Leger HIGH SPEED CURRENT COLLECTION [75] Inventor: Roland Leger, Paris, France [73] Assignee: Faiveley S.A., Saint Ouen, France [22] Filed: May 8,1972

[21] Appl. No.: 250,993

[30] Foreign Application PriorityData May 10, i971 France 71.16881 52 us. Cl. f. 191/66 51 Int. Cl B60l 5/22 [58] Field of Search 191/45, 47, 48, 49, 50, 54, l9l/55, 56, 59, 59.1, 65-70 [56] References Cited 1 UNITED STATES PATENTS 1,159,536 ll/l9l5 Schutte l91/63 [451 Mar. 5, 1974 2/1970 Mohring l9l/68 2/1941 Schaake ..l9l/55 Primary Examiner-Gerald M. Forlenza Assistant ExaminerD. W. Keen [5 7 ABSTRACT The coupling between a high speed electrically powered vehicle and an overhead catenary wire current distribution system is enhanced by elastic coupling means which parallels and thus provides for uniformity of movement of oppositely disposed ends of a support portion of a pantograph-bow collector linkage system when the inclination of the system to the horizontal exceeds a predetermined limit.

10 Claims, 3 Drawing Figures PATENTED 5 SHEU 1 BF 2 PATENTED 5 SHEET 2 [IF 2 HIGH SPEED CURRENT COLLECTION BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the transfer of current to and/or from an overhead catenary distribution system and particularly to such current transfer during high speed motion between the current collector and the catenary. More specifically, the present invention relates to improved support apparatus for the electrical pick-up devices employed on high speed electrically powered vehicles wherein means is provided to compensate for the effects of transverse movement of the catenary as the vehicle traverses curves and crossing points. Accordingly, the general objects of'the present invention are to provide novel and improved methods and apparatus of such character.

2. Description of the Prior Art In copending U.S. Pat. application Ser. No. 058,971, filed July 28, 1970, now U.S. Pat. No. 3,730,312, and entitled Method and Apparatus for Transferring Electrical Energy to High Speed Apparatus, an improved system for high speed current collection isdisclosed. U.S. Pat. No. 3,730,312 is incorporated herein by ref erence. In the referenced patent the improved current collection system is characterized by separate compensation for low amplitude vertical displacements of a pantograph-bow collector assembly,'resulting from dynamic movements of the catenary, and high amplitude vertical displacements of the collector assembly, resulting from the static profile of the catenary. Considering FIG. 1 of the referenced patent, the upper or small elastic pantograph 26 provides the dynamic compensation while the large or lower elasticpantograph provides for thc static compensation. The invention of U.S. Pat. No. 3,730,312 resides principally in the judicious combination of the two elastic compensation means in such a manner as to avoid interaction between-these means by careful selection of damping conditions.

In practice the invention of U.S. Pat. No. 3,730,312 has led to the use, for the upper elastic or low amplitude dynamic compensation system, of resilient means having a much greater flexibility than previously employed similar devices; increases in the degree of elasticity being on the order of 10 to times. High speed trials performed through the courtesy of the French National Railways have demonstrated the operability and substantial technical advancement achieved through the use of the invention of Pat. No. 3,730,312. These tests have also revealed that, above certain high speeds on curves and at crossing points, the relative transverse movement of the catenary tends to load one end of the pantograph-bow collector system more then the other end so as to cause the'current collector assembly to assume an exaggerated inclination to the horizontal.

Restated, tests have revealed that the advantages of the invention of U.S. Pat. No. 3,730,312 could not be fully utilized due to the flexibility of the resilient means, employed for the upper support of the overall pantograph-bow collector system, which is subjected to the full load unbalance during the high speed traversal of curves and crossing points.

7 SUMMARY OF THE INVENTION The present invention overcomes the above briefly discussed disadvantage of the prior art by taking advantage of the fact that in practice the pantograph head of the current collector of the high speed current transfer device of US. Pat. No. 3,730,312 is supported at a pair of points located adjacent its respective ends. In accordance with the present invention the two vertically movable ends of a pantograph head are interconnected; the interconnection preferably being accomplished with paralleling means having a degree of elasticity. The interconnection results in the uniformity of movement of the two points; uniformity of motion being delayed until the inclination of the pantographbow collector to the horizontal exceeds a predetermined limit when elastic connecting means are employed.

In copending U.S. application Ser. No. 236,874, filed Mar. 22, 1972 and entitled Improvements in High Speed Current Collection," an improvement to the current collections system of above discussed U.S. Pat. No. 3,730,312 is disclosed. Application Ser. No. 236,874, which is also incorporated herein by reference, teaches the separate compensation for low frequency movements arising from impacts of the pantograph-bow collector against first hard points" of the catenary, where it is suspended from the support poles, and the higher frequency dynamic movements arising from impacts of the pantograph-bow collector against secondary hard points of the catenary at the auxiliary suspension points of the catenary between the two successive support poles. Accordingly,.the invention of application Ser. No. 236,874 has led to the use of three superimposed'elastic systems for supporting the pantograph-bow collector system.

The present invention can be applied to the system of application Ser. N."236,874 wherein it may be employed for either the intermediate or upper of the three resilient support subsystems.

In the high speed current collection system of referenced copending application Ser. No. 236,874 the intermediate elastic system will support the pantograph head and the upper elastic system will support the collecting strips which contactthe catenary. When employing the present invention it is advantageous to unify the movements of the support points of the pantograph head at its ends whereby the sliding catenary collecting strips are left free to niove untiltheir inclination brings them to rest on the plate or against a stop integral with the plate.

BRIEF DESCRIPTION OF THE DRAWING The present invention may be better understood and I its numerous objects and advantages will become apcoupling device; and

FIG. 3 is a schematic, perspective view of a third embodiment of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS It is to be observed that in disclosing the present invention, the elements of the prior art as exemplified by the referenced patent and copending application have been omitted from the drawing in the interest of clarity. Thus, with reference to FIG. 1, the invention includes a pantograph head 1 which includes the usual lifting horns 2 and 3. Head 1 is suspended, typically above the lower resilient or static compensation means, adjacent its ends by plungers 4 and 5. Plungers 4 and 5 are respectively movable within spring boxes 6 and 7. Spring boxes 6 and 7 are, in turn, fixed to the lifting device (not shown). The sliding strips which collect current from the catenary have similarly not been shown. Plungers 4 and 5 define differential area pistons which are supported, by helical springs 8, from the base of the spring boxes. The upper or large diameter portion of each plunger is machined to define a rack 10 which engages a pinion gear 12. The two pinions 12 are interconnected by bar means 13 which may be rigid or elastic. In the case where the connecting bar is rigid it can, if desired, be divided into two portions interconnected by an elastic coupling schematically indicated at 14. Elastic coupling 14 may be of the type well known in the art and will not be described further herein.

The pinions 12 are located in housings which either comprise part of or are connected to the spring boxes 6 and 7; the pinions being rotatably mounted in a manner which has not been shown in the drawing in the interest of clarity. Any movement of either of plungers 4 or 5 will be accompanied by a corresponding movement of the other plunger. However, there may be a hysteresis as a result of the elasticity of the connection 13 or the coupling 14.

The embodiment of FIG. 2 is similar to that of FIG. I with the principal exception that the spring boxes 6 and 7 have been replaced by sealed cylinders containing a suitable fluid. The plungers 4 and 5 each include piston portions 15 and 16 which respectively divide cylinders 6 and 7 into a pair of oppositely disposed chambers. Opposite chambers of the cylinders 6 and 7 are interconnected as shown by means of conduits 17 and 18. If desired, damping means may be provided in the FIG. 2 embodiment by the incorporation of restricting apertures in pistons 15 and 16 or, as shown, by the connection of an adjustable throttle device 19 in one of conduits 17 or 18. In FIG. 2 the adjustable throttle device has been shown schematically as a needle valve.

The embodiment of FIG. 3 is similar to the FIG. 1 embodiment with the principal exception that the spring boxes 6 and 7 respectively carry supports 20 and 21; the supports typically being attached to the spring boxes by welding. A rigid or elastic bar 22 having parallel right-angle bends at its ends, the bends defining rods 23 and 24, is threaded through holes located adjacent the outwardly disposed ends of supports 20 and 21. The

free ends of the parallel rods 23 and 24 are pivotably connected to further rods 25 and 26; rods 25 and 26 either being rigidly connected to pantograph head 1 or, preferably, to the upper portion of plungers 4 and 5 in such a manner as to be parallel to one another as shown.

In the FIG. 3 embodiment vertical movement of one end of pantograph head 1 will result in the rotation of bar 22 about its geometric axis. Rotation of bar 22 will be transformed into a vertical translational movement of the other end of head I. As in the FIG. 1 embodiment, it is possible to incorporate an elastic coupling in the bar 22 of the FIG. 3 embodiment.

While preferred embodiments have been shown and described, various modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Thus, the three embodiments discussed relate to the use of spring boxes or the like and the oscillation of the arch or plate in a vertical plane perpendicular to the track on whichthe high speed vehicle is traveling". The disclosed embodiments are those which require the least number of structural changes to the present installations if the invention is to be incorporated therein. However, it is believed that those skilled in the art can adapt the invention to support means comprising other than plunger devices such as, for example, arms pivotable in vertical planes parallel to the direction of the track; the pivotable movements of such arms being capable of being unified by the same or equivalent means to those described above. Accordingly, it is understood that the present invention has been described by way of illustration and not limitation. v

What is claimed is:

1. In a pantograph high speed current collection system for engaging an overhead supply line, the system employing a pantograph-bow collector assembly resiliently supported vertically adjacent its ends, the improvement comprising:

means simultaneously constraining the movements of the two supported ends of the pantograph-bow collector assembly whereby said supported ends displace simultaneously parallelly with one another throughout at least part of the permitted range of vertical movement of the assembly.

2. The apparatus of claim 1 wherein said constraining means comprises:

first gear means carried by each end of the vertically movable bow collector assembly; second gear means, the position of said second gear means with respect to said collector assembly being fixed, each of said second gear means engaging a respective one of said first gear means; and

coupling means interconnecting said second gear means.

3. The apparatus of claim 2 wherein each of said first gear means includes a gear rack and wherein each of said second gear means includes a pinion gear operatively connected to an associated rack and wherein said coupling means comprises:

first axle means connected to the pinion gear of a first of said second gear means; second axle means connected to the pinion gear of the second of said second gear means; and elastic coupling means interconnecting said axle means. 4. The apparatus of claim 3 further comprising? spring box means resiliently coupling the ends of the bow collector assembly to a lower support means, said spring box means each housing a spring damped plunger connected to said assembly, each plunger defining the rack of said rack and pinion means. 5. The apparatus of claim 1 wherein said constraining means comprises:

hydraulic means connected to each end of the movable bow collector assembly, each of said hydraulic means including a piston movable within a cylinder filled with hydraulic fluid, said pistons dividing said cylinders into said first and second chambers; and conduit means interconnecting the piston defined chambers of said hydraulic means, said conduit means connecting the first chamber in one hydraulic means cylinder to the second chamber of the second hydraulic means cylinder and the first means resiliently coupling the ends of the bow collector assembly to a lower support, said resilient coupling ,means defining said hydraulic means cylinders.

8. The apparatus of claim 1 wherein said constraining means comprises:

mechanical linkage means connected to each end of the movable bow collector assembly; and

means interconnecting said linkage means, said interconnecting means producing corresponding movement of said assembly ends.

9. The apparatus of claim 8 wherein said interconnecting means is a torsion bar, the movementsof said assembly being converted into rotational force applied to said torsion bar by said linkage means.

10. The apparatus of claim 9 further comprising:

spring box means resiliently coupling the ends of the bow collector assembly to a lower support. 

1. In a pantograph high speed current collection system for engaging an overhead supply line, the system employing a pantograph-bow collector assembly resiliently supported vertically adjacent its ends, the improvement comprising: means simultaneously constraining the movements of the two supported ends of the pantograph-bow collector assembly whereby said supported ends displace simultaneously parallelly with one another throughout at least part of the permitted range of vertical movement of the assembly.
 2. The apparatus of claim 1 wherein said constraining means comprises: first gear means carried by each end of the vertically movable bow collector assembly; second gear means, the position of said second gear means with respect to said collector assembly being fixed, each of said second gear means engaging a respective one of said first gear means; and coupling means interconnecting said second gear means.
 3. The apparatus of claim 2 wherein each of said first gear means includes a gear rack and wherein each of said second gear means includes a pinion gear operatively connected to an associated rack and wherein said coupling means comprises: first axle means connected to the pinion gear of a first of said second gear means; second axle means connected to the pinion gear of the second of said second gear means; and elastic coupling means interconnecting said axle means.
 4. The apparatus of claim 3 further comprising: spring box means resiliently coupling the ends of the bow collector assembly to a lower support means, said spring box means each housing a spring damped plunger connected to said assembly, each plunger defining the rack of said rack and pinion means.
 5. The apparatus of claim 1 wherein said constraining means comprises: hydraulic means connected to each end of the movable bow collector assembly, each of said hydraulic means including a piston movable within a cylinder filled with hydraulic fluid, said pistons dividing said cylinders into said first and second chambers; and conduit means interconnecting the piston defined chambers of said hydraulic means, said conduit means connecting the first chamber in one hydraulic means cylinder to the second chamber of the second hydraulic means cylinder and the first chamber of the second hydraulic means cylinder to the second chamber of the first hydraulic means cylinder.
 6. The apparatus of claim 5 wherein said conduit means comprises: a first hydraulic coupling; a second hydraulic coupling; and damping means interposed in said first hydraulic coupling.
 7. The apparatus of claim 6 further comprising: means resiliently coupling the ends of the bow collector assembly to a lower support, said resilient coupling means defining said hydraulic means cylinders.
 8. The apparatus of claim 1 wherein said constraining means comprises: mechanical linkage means connected to each end of the movable bow collector assembly; and means interconnecting said linkage means, said interconnecting means producing corresponding movement of said assembly ends.
 9. The apparatus of claim 8 wherein said interconnecting means is a torsion bar, the movements of said assembly being converted into rotational force applied to said torsion bar by said linkage means.
 10. The apparatus of claim 9 further comprising: spring box means resiliently coupling the ends of the bow collector assembly to a lower support. 